Chain hoist



Aug. 29, 1961 E. E. HIMEL, JR

CHAIN HOIST 3 Sheets-Sheet 1 Filed June 11, 1958 Aug 29, 1961 E. E.HIMEI., 1R 2,998,277

CHAIN HOIST Filed June l1, 1958 3 Sheets-Sheet 2 .lll

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Aug. 29, 1961 E. E. HIMEL, JR 2,998,277

CHAIN HoIsT Filed June ll, 1958 3 Sheets-Sheet 3 H IO @ya @7c/0.

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United States Patent 2,998,277 CHAIN HOIST. Edmond E. Hlmel, Ir., 5031St. Anthony Ave.,

New (Means, La. Filed Jnne'1`1,e1958, Ser. No. 741,295 Claims. (Cl.294-75) This invention relates to chain hoists of the type used forhandling sugar cane or the like and has `for an object to provide ahoist of the yabove type having novel and improved characteristics.

Another object is to provide, in Ia hoist of the above type, novel andimproved trip mechanism adapted to permit the operator of the hoist torelease the load from a remote point.

Another object is to provide a remote controlled chain release fordropping `the chains Ifrom the hoist.

Another object is to provide a safety trip constructed and arranged toprevent accidental actuation of the trip mechanism.

Other objects and advantages will be apparent as the nature of theinvention is more fully disclosed.

`In accordance with the present invention one or more sling chains areattached to hooks depending from a spreader bar attached to the hoist.The hooks are provided with trip devices for dropping the chain whendesired. This trip device is connected to be actuated by a remotecontrolled iluid pressure device mounted on the spreader har.

The sling includes a -frame having a hook for carrying the sling end ofthe chain and a guide to hold a chain loop around the load to he lifted.Trip means is provided for the hook which is adapted to be actuated by atrip line cam'ed on a reel on the spreader bar and having remotecontrolled lock means -to cause the reel to apply tension to the line-for tripping the hook when the load is to be released. I'he trip linelock is adapted to be actuated from the hoist operators cabin so thatother attendants :are not required for releasing the load. This alsoavoids the possibility of injury to an attendant who would otherwise -berequired to stand in a position to trip the hook manually.

A safety latch is also provided to prevent the trip line from releasingthe hook prematurely. This safety latch may take the form of a ring orhook attached to the frame orto the chain and releasable in response toa predetermined pull on the trip cord, or a resilient member associatedwith the trip device which is adapted to resist the pull of the tripline until the pull exceeds a predetermined value.

The speciic nature orf the invention will be better understood trom thefollowing description, taken in connection with the accompanyingdrawings in which certain embodiments have been set 4forth for purposesof illustration.

In the drawings:

FIG. 1 is a side elevation of a hoisting apparatus embodying theinvention;

FIG. 2 is a detail view of a further embodiment of the hook mechanism;

FIG. 3 is a ventical section taken on the line 3--3 of FIG. 2;

FIG. 4 is a longitudinal vertical section through a safety latch hookembodying the invention;

FIG. 5 is a transverse vertical section taken on the line 5--5 orf FIG.4;

FIG. 6 is a transverse horizontal section taken on the line 6-6 of FIG.4;

FIG. 7 is a detail view of the hook in trip position;

FIG. 8 is a vertical longitudinal section showing the guide unit;

'E IQ. 9 is a vertical transverse section through the reel;`

FIG. l0 is a vertical section taken on the line 10--10 of FIG. 9;

FIG. 11 is a detail of a further embodiment of the safety tripmechanism;

FIG.12 is a horizontal section taken on the line 12-'12 of FIG. 13illustrating a further embodiment of the chain release mechanism; and

FIG. 13 is a vertical longitudinal section taken on the line 13-13 ofFIG. l2.

Referring to the drawings more in detail the invention is shown in FIG.1 as embodying a spreader bar 10 which is connected Ito a hoist cable byrods or cables 11 and which carries a pair of sling chain hooks '12 onwhich sling chains 13 are carried. The bar 10 also carries trip linereels 15, duid pressure cylinders A16 for actuating the sling chainrelease mechanisms, a pump 17 -for supplying fluid under pressure to thecylinders 16 and a motor 18 for actuating the pump 17, and a reservoir30 for the pressure uid.

Each hook 12 is pivoted to a bracket 20 attached to the spreader bar 10and carries a latch 21 adapted to prevent the chain from accidentallyfalling from the hook.

. A lin-k Z2. is pivoted to the hook 12 and is attached to a releaseline 23 which passesover a guide pulley 24 on the bar 10 and isconnected to a piston rod 25 of a piston 26 sliding in the cylinder 16.

A link 27 is connected between the latch 21 and the link 22 to retractthe latch 21 when the link 22 is actuated.

Normally a link or end ring of the chain 13 is carried by the hook 12and is secured by the latch 21 as shown at the right in FIG. l.` Whenthe chain is to be released, for example, after the load has beendropped, fluid pressure is applied to the cylinder 16 to actuate thepiston 26 for retracting the line 23, thereby pulling upwardly on thelink 22 to pivot the hook 12 to the position shown at the left inFIG.I1. At the same time the latch 21 is retracted by the link 27 torelease the chain 13 and allow the chain to drop from the retracted hook12.

The fluid pressure to the cylinder 16 is controlled from the hoistoperators cabin or otherremote point by an electrically controlled valve28 in pressure line 29 leading from the pump 17 to each cylinder 16. Thepump 17 may be controlled automatically to maintain the requiredpressure in the line 29 as by a pressure controlled switch, not shown,in the energizing circuit of the motor 18. Pressure fluid for operatingthe pistons is derived from the reservoir 30. A cable 31 supplies powerto actuate the motor 18 and the various remote controlled valves 28.Obviously the valves 28 may be omitted in which event both hooks aretripped in unison when power is supplied to the motor 18 which may becontrolled from the opera-v tors cabin or a manually operated lever (notshown) may be connected to actuatc the line 23 in place of or inaddition to the power control above described.

The chain 13 passes through a guide 35 (FIGS. 1 and 8) having a curvedsection 36 over which the chain can slide and having a pawl 37 pressedby a spring 38 into engagement with the chain on the member 36. The pawl37 is shaped to be automatically retracted when the chain is pulledthrough the guide 35 in a direction to grip the load but to clamp thechain against reverse movement.

The chain .13 after passing through the guide 35 passes around a load40. The end ring 41 of the chain is hooked over a hook 42 (FIGS. 1 and 4to 7) which is pivoted to a frame 43. The trame 43 is connected to theguide 35 by links 39.

The hook is formed with a bifurcated end having lingers 44 and 45forming a slot 46 therebetween. A latch 47 is pivoted by a point 52 tothe frame 43 and is formed with slots 48 and 49 adapted to receive thelingers 44 and 45 respectively, of the hook 42 so as to close the end ofthe slot 46, when the latch 47 is in latching position as shown in FIG.4. A Spring 50 engaging an arm 51 on the latch 47 holds the latch inthis position.

A snap hook 54 attached to a trip line 55 is adapted to be snapped overthe finger 45 into the slot 46, with the hook 42 in load carryingposition. When the line 55 is pulled the snap hook 54 engages the latch47 and retracts the same Afrom the iingers 44 and 45 of the hook 42,thereby allowing the hook 42 to pivot and drop the end of the chain 1'3for releasing the load.

In order to prevent accidental tripping of the latch 47 a pair of springarms 56 are held in the frame 43. These arms 56 extend partly around thepivot 52, and bear against a cam surface 58 formed in the frame 43 whichis shaped to limit the bending movement of the arms 56. The arms 56extend upwardly in front of the latchL 47 arid across the slot 46 sothat the hook 54 cannotengage the latch 47 until the arms 56 have beenflexed. The arms are made sufficiently stili to prevent accidentaltripping of the latch but not so stift` but that a substantialpredetermined pull on the line 55 will flex the arms and permit the hook54 to engage and trip thelatch 47.

The line 55 is reeled upon the reel 15 on the bar 10 which is springloaded to keep the line 55 under tension as the chain 13 is raised orlowered. The reel 15 (FIGS. 9 and l0) is provided with a spring 60 forthis purpose and with a latching mechanism comprising a solenoidoperated latch 61 comprising a latch arm 62 which is adapted to engagenotches 63 in the reel which are shaped to lock the reel againstrotation in the direction to unwind the line 55 but to permit rotationof the reel in the Winding direction. The latch arm 62 is pivoted at 64and carries an operating arm 65 connected by a tension spring 66 to theplunger 67 of a solenoid 68. The solenoid 68 is energized by a suitablecircuit not shown, and is connected to be operated from the operatorscabin. The arm 62 is normally retracted to permit free operation of thereel 15. When the solenoid 68 is energized the arm 62 is brought intolatching engagement with a notch 63 of the reel 15 to lock the reelagainst rotation.

When the load is being carried by the chain as at the right in FIG. 1the spring 60 causes the reel 15 to maintain the trip line 55 tight butdoes not exert a tripping force. When the load is lowered, into place ason a truck or on the ground the bar is further lowered by the hoistoperator to an extent to produce slack in the chain 13. The spring reelnevertheless keeps the trip line 55 tight. 68 to lock the reel 15 andprevent further lengths of trip line from being unreeled. v

The operator then raises the bar 10. Since the reel is vlocked the line55 is pulled upward by the upward motion of the bar 10 with a forcesuicient to flex the safety arms 56 and trip the latch 47 therebyallowing the hook 42 to pivot to load releasing position. The bar `10 isthen raised to pull the end of the chain out from the load in the usualmanner. When the solenoid 68 is released the reel 15 reels in line 55which is now free, until a stop 69 is reached.

FIGS. 2 and 3 show a modiied form of hook and chain release mechanism.

Referring to these gures, an arm 70 carrying double hooks 71 and 72 ispivoted to the end of a spreader bar 10a, similar to the spreader bar 10above described. The hooks 71 and 72 are adapted to engage links ofhoisting chains 13 or end rings of such chains as in the case of thehooks 12 described in connection with FIG. 1.

For releasing the chains from the hooks 71 and 72 cam plates 74-areprovided carrying a pin 7S which is slidable vertically in a slot 76 inthe arm 70. 'Ihese cam plates 74 are attached to a trip line 23acorresponding to the trip line 23 of FIG. 1 and connected to be actuatedmanually or yautomatically as above described.

This double hook is adapted to carry two hoisting chains which may passaround the same load or separate The operator now actuates the solenoidlloads as desired. Both chains are automatically released Iby actuationof the trip line 23a when the operator desires to drop the chains.

FIG. l1 illustrates an additional safety latch which may be used inconnection with the hook releasing mechanism illustrated in FIGS. 4 to 7to supplement the action of the spring arms 56. In some instances,however, the spring arms '56 may be omitted when the latch mechanism ofFIG. 11 is used provided the additional safety factor is not necessary.I

Referring now to FIG. 1l the trip line 55a is similar to `the trip line55 above described and is actuated in the Same manner. The trip line 55ais attached to a latch hook 80 which in tum is hooked into a springmember 81 comprising a loop portion 82 and a pair of spring arms 83which are normally held closed by spring action, but are adapted to beflexed sutiiciently to allow the passage of the latch hook 80 whensuicient force is applied to the line 55a. The loop portion 82 of thespring member 81 is connected by a link 85 to a link of the chain 13 sothat the Vchain 13 is caused to resist the pull of the trip line 55auntil the pull becomes suiciently strong to ex the arms 83 of fthespring member 81 and thereby release the latch hook 80. A latch hook54a, similar to the hook 54 above described, is connected to the hne 55aby means of a line 86 which is normally slack, as shown in FIG. 11, soas not to exert a pull on the hook 54a. Hence there will be no trippingtierce exerted until suticient tension has been applied to the line 55ato first release the latch( hook 80. A tension is then app-lied throughthe line 86 to the hook 54a which is connected to trip the latch member47 as above described.

FIGS. 12 and 13 illustrate a modied type of chain releases. In thesefigures the hook 12 of FIG. 1 is replaced by an inclined plate 90disposed between opposed channel members 91 forming a spreader bar 10above described.

The plate 90 is provided at its end With a slot l92 which is adapted toreceive the link of the hoist chain 13 for securing the same.

For removing the chain from the slot 92 a uid pressure cylinder 94 isprovided vwhich is carried on the linclined plate and is provided with apiston rod 95 having a head 96 which is adapted to ybear against thechain 13 and push the chain out of the slot 92 when the piston rod isextended. The cylinder 94 is connected to be actuated by iluid pressurein a manner similar to the cylinders 16 described in connection withFIG. 1. l

Although certain specific embodiments of the invention have been shownand described for purposes of illustration, it is to be understood thatthe invention may be adapted for various uses and may be embodied invarious forms as 'will be apparent to a person skilled in the art.

What is claimed is:

l. A sling hoist with remote controlled trip, comprising a bar adaptedto be suspended from a hoisting cable, means on said lbar to receive asling chain, a hook and guide assembly including a hook having apivotally mounted load engaging portion which is adapted to receive theend of the sling chain and to maintain a loop of said chain around asuspended load, a retractable hook latch connected to hold said hook inload carrying position and when retracted releasing said hook to pivotto chain releasing position, a pull member engageable with said latch toretract the same, a trip line connected to said pull member, a reelcarrying said trip line and mounted on said bar, spring means normallyactuating said reel in a direction to hold said trip line under tensionas the sling Ichain moves relative to said bar, a latch member adaptedto latch said reel against rotation in the direction to unwindsaidlineand remote controlled means to` actuatesaid latch member to latchsaid reel whereby lifting of said bar and reel relative to said hook andguide assembly causes '.saidtrip line toexert apull on said. pull nenberfor reti-acting said hook latch and releasing the oad.

2. A device as set forth in claim 1 in which said reel latch comprises asolenoid operated latch amm adapted to engage notches in said reel andconnected to be actuated from a remote point.

3. A device as set `forth in claim 1 in which a spring member comprisingfa pair of spring arms extending parallel to said hook latch is disposedin advance of said hook latch in a position to receive the pull off saidpull member.

4. A device as set orth claim; 1 in which said hook carries a bifurcatedarm having a pair of ingeas forming la slot therebetween, said hooklatch is provided with slots receiving said fingers to close the end ofsaid rsft slot, and said pull mennber is disposed in said last mentionedslot in a position to engage and retract said latch.

5. A device as set forth in claim 1 in which a releasalble link isattached to said chain and to Asaid 'tnp line to 6 take the pull of saidftrip line suicient fofrce is applied to release said link, therebypreventing the pull of said line 'from being applied to said pull memberwhile said link is engaged.

References Cited in the le of this patent UNITED STATES PATENTS

